Gun data computer having spot correction means



Feb. 16, 1954 w BO O l N ETAL GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Shegts-Sheet l CLOUD is WITCH nzmuru AL Tl TUDE CONVERTER SWITCH AL 17 run: 1 CONVERTER RADAR 53 ELEVATION PIG ALTITUDE SLANT 7 DISTANCE To RAMs/m: DEV/CE F l6. l2

ATTORNEY FeB. 16(1954 w. H. BOGHOSIAN ET AL ,6

GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet 2 FIGS r 4 408 425 mm 447 NETWORK F OR Y COORD/NA TE NETWORK FOR H COORDINATE POWER 452 J #HBOGHOS/AN INVENTORS 8.7. WEBER BY E ATTORNEY Feb. 16, 1954 W.-H. BOGHOSIAN ET AL 2,669,386

GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet 5 nmczr Mr: uznw .uvo mun ser 455 nun" FOR r comm/Ar:

TARGET RATE METZ'R Am HAND SET .456

RATE FM H COORDINATE W. H. BOGHOS/AN lNl/EN TORS: h. 0. 0c

5.; WEBER A T TORNE Y Feb. 16, 1954 w. H. BOGHOSIAN ET AL ,6 9,

"G'JN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet 4 SECOND DERIVATIVE NETWORK FOR P EOORDINA TE SECOND DERIVATIVE NETWORK FOR H COORDINATE WHBOGHO-S/AN INVENTORS: h. G.OCH

B. 7. WEBER A 7' TORNEY F 16, 1 w. H. BOGHOSIAN ET AL 2,669,3

GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheefs-She't 5 V 'B. [WEBER ATTORNEY GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet 6 nil-i EOGHOSMN /N l/EN T 0R5 H. 6.0C'H

By I B. 7.' WEBER A T TORNEY Feb. 16, 1954 w. H. BOGHOSIAN ETAL 2,669,336

GUN DATA COMPUTER HAVING SPOTCORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet '7 m4 I065 H207 MHBOOg/JOSIAN INVENTORS: 1-1.0. 807 527 5,7: WEBER ATTORNEY Feb. 16, 1954 GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 FIG. /3A

16 Sheets-Sheet 9 N FIG/38 N C A A W a X; l

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GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 1s Sheets-Sheet 10 W H. BOGHOS/AN H. a. OCH By a. r. WEBER maul-um,

INVENTORSI QKQ H .1 E NFRQ h u mo\\ 3% at 23 mm W \w! R A ER W m mwwos B: Q NE 2 3 3 Y $3 ,3 .H 3 6E A TTORNE V Feb. 16, 1954 W. H. BOGHOSIAN ETAL GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheet FIG. /6

s-Sheet 11 H. BOGHOSIAN INVENTORS: OCH

WEBER AT TORNE Y 6, 1954 w. H. BOGHOSIAN ETAL ,669,386

GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS 16 Sheets-Sheet 15 Filed June 26, 1946 ATTORNEY "(H.BOGHOS/AN hi6. OCH B.T. WEBER BY @roxes:

Feb. 16, 1954 w. H. BOGHOSIAN ET AL 2,669,386 GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 v 16 Sheets-Sheet l4 2; gggflosulv INVENTOPS" B: WEBER ATTORNEY,

6, 5 w. H. BOGHOSIAN ETAL 2,669,386

GUN lfiATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 26, 1946 16 Sheets-Sheet 15 FIG. 24

W H. BOf/HOSIAN TOPS: 11.0. 0c WVEN e. r. WEBER A T [ORNE V 1954 w. H. BOGHOS IAN ETAL. 2, ,386

GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS Filed June 1946 16 Sheets-Sheet 1s B. 7.' WEBER A I romvm Patented Feb. 16, 1954 GUN DATA COMPUTER HAVING SPOT CORRECTION MEANS William H. Boghosian, Summit, Henry G. Och, Short Hills, and Bruce T. Weber, Summit, N. J., assignors to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application June 26, 1946, Serial No. 679,351

4 Claims. 1

This invention relates to gun data computers and particularly to electromechanical computers.

The object of the invention is the provision of means for making small arbitrary changes in the magnitudes of the quantities representing the most important factors in the data. These means are generally known as spotting controls or spots.

A feature of the invention is a range spot for making a small arbitrary change in the magnitude of the quantity representing the slant distance from the point of observation to the present position of the target, this change either being proportional to the magnitude of the quantity, thus producing a percentage change in the quantity or, if desired, the change may be absolute in magnitude.

Another feature of the invention is an altitude spot for making a small change in the magnitude of the quantity representing the altitude or height of the present position of the target above the horizontal plane containing the point of observation, this change either being arbitrary or proportional to the difference in altitude between the height finder and the reference point of the battery.

Another feature of the invention is an azimuth or train spot graduated in terms of a small angular change in the angle of azimuth or train and producing a change in the quantity representing the linear transverse components of the projected position of the point of fire.

Another feature of the invention is an elevation spot, graduated in terms of a small angular change in the elevation angle or quadrant elevation and producing changes in the quantities representing the horizontal range and linear elevation or height of the projected position of the point of fire, and a change in the quantities representing the time of flight of the shell, to compensate for the effect on the quantity representing the time of flight of the change made in quadrant elevation.

A further feature of the invention is a fuse number spot for making a small change in the quantity representing the fuse number, which will be proportional to the fuse number, thus producing a percentage change in the quantity.

Other features and advantages of the invention will be apparent from the specification and drawings, in which:

.Fig. 1 schematically shows the observing equipment;

Fig. 2 schematically shows a summing amplifier;

Fig. 3 shows amplifiers associated with Fig. 1;

Fig. 4 schematically shows the first derivative and smoothing networks;

Fig. 5 schematically shows the target rate meters and apparatus for supplying quantities proportional to hand set rates;

Fig. 6 schematically shows the second derivative and smoothing networks;

. Fig. '7 schematically shows equipment for computing and indicating the gun order for azimuth or train and the fuse number;

Fig. 8 schematically shows equipment for computing and indicating the time of flight of the shell and the gun order for quadrant elevation;

Fig. 9 schematically shows a motor modulator amplifier;

Figs. 10 and 11 schematically show equipment for controlling plotting boards associated with the computer;

Fig. 12 shows the relationships of Figs. 1 to 11; and

Figs. 13A, 13B, 13C, 13D, diagrammatically show the geometrical relationships involved;

Fig. 14 is a top view of a board, associated with the computer, for plotting the horizontal position of the target;

Fig. 15 is a perspective view of the horizontal board;

Fig. 16 is a view in part section along the line l6-I6 of Fig. 14;

Fig. 17 is a top view of one type of plotting p Fig. 18 is an end view of the pen shown in Fig. 17, and a section along line l8--I8, Fig. 14;

Fig. 19 is another end view of the pen shown in Fig. 17;

Fig. 20 is a front view of an automatic marking device;

Fig. 21 is a top view of the device shown in Fig. 20;

Fig. 22 is a rear view of the device shown in Fig. 20;

Fig. 23 is a top view in part section of a board, associated with the computer, for plotting the vertical position of the target;

Fig. 24 is a partial end view of the board shown in Fig. 23;

Figs. 25, 26 are side views in part section of the pens used with the board of Fig. 23; and,

Fig. 27 is a section of the board shown in Fig. 23 showing the paper sheet take up. i

The slant distance to the target may be continuously observed by a radar, or an optical range finder; or the height of the target may be continuously observed by a radar or an optical height finder.

In Fig. 1,"a grounded source of power l is connected through a resistor 2 and the winding 30! of potentiometer PT3 to ground. The brush of potentiometer PT3 is connected to the slant distance shaft of a radar, and is moved by the shaft to select a voltage with respect to ground proportional to the slant distance; and is connected through resistor 5, connection 6 and resistor 3! 5, Fig. 3, to the input circuit of amplifier 302, of the type shown in Fig. 2.

If an optical range finder is used, a synchronous transmitter driven bythe ,slant distance shaft of the range finder ,is connected to the synchronous receiver 1, Fig. 1. :Thereceiver drives the center dial 8, of three concentric dials 8, 0, 10. The motor H, through the speed reducing device i2 and gears i3, drives .theouter dial H3. The operator adjusts the device [2 until the dial i is turning in synchronism. with the dial 3.

-A grounded, source-of, power ;l6-;is ;-eqnnected through resistor l and the windingtfit of. potentiometer PTG to ground. The brush of po- ,tentiometer PTfi is connected to the: device 12 and is moved to select avoltage with ;respect to ground p op r i na Q-t erslan di tan h brush is connected ;-through resistor 18, connection hand resistor 315,-Fig. 3, to the input circuit ,-of,- ,1 amplifier 302.

When either of the-brushes of; potentiometers PT3 or -PT6, of Fig. 1 ,,is in u se, the other brush preferably; disconnected, or rotated to the grounded endof the associated winding.

The amplifier; shown;in l3ig. 2 employs three vacuum tubes 220, 221, 228 having the-usual cath de e t d b bea r e n s cgnnected ;to a1 suitable source oiepower (not shown). The vacuum tube 220 is preferably a v,twin triode havme; the cathode connected through, a variable resistor 204 and resistor 205 to ground. A grounded source, of. positive{ potential 2 05 is connected ;,to.;the anode, and thetcontrol electrode is ,,connected, to the junction ,of resistors fifi i, 205. As disclosed ,in ,United ,States-Patent 2,308,997, January 19, 1943, S, EFL/11191; this connection stabilizes the twin triode against variations in cathode emission.

Theinput terminalwzflfi, is connected to-the control electrode of the left-hand section of the twin triode 226. The anode of this section is connected to the control electrode of the pentode 227 ,by,.an interstage coupling network, of the type disclosed in United States ,Batent 1,751,527, March. .25, 1,930, I-I. ,Nyguist, including resistors 201, 200, 200 and the sources of power 2|0, 2H. Resistor 212 ,and capacitor 2,!3, connected; in serial relationship across the input.,,c ir.cuit of pentode 227 correct forany. phase shifts in the amplifier due to parasitic capacitances.

1 The, ,cathode vand,,suppressor grid "of the pentode 221 are connected to ground, and the screen grid is connected to a grounded source of power 214.

The anode of the .pentode;22'l is,coupled to the control grid of the beam power,vacuum tube..228 by a coupling network including resistors -2|5,

-2l6,,2l,1 and the sources. of power 2H8, 219.

Thecathode, and-beamscreen, of thetube228 are connected to the negative pole ;of the grounded sourcc of. power 220. The screengrid isgrounded through resistor ,22 l. The anode is connected v through resistor ,222-,,to ,the pgsi tive pole of the groundedsource of power 223.

The biasing voltage applied to the ;control electrode of tube 228, the resistanceof resistor 222 and the. magnitudes of the; potentials ot the sources 220, 223 are so selected that, when no signal voltage is applied to the input terminal 200, these elements form a balanced bridge and no potential difference-will be produced across ,theputput terminals 220, ;2-25. If desired, a potentiometer (not shown) may be connected to supply a small adjustable potential to the input terminal 200 so that, in the absence of a signal voltageapplied to the terminal 200, the potential diiference between the output terminals 224, ,2 25 rnaybe'adjusted precisely to zero.

I A potentialdivider, such as the winding of a potentiometer, ortwo resistors in series, may be 'connectedacrosstthe output terminals 224, 225. The brushof thisfipotentiometer, or the junction of the, resistors, is,connected to the input terminal 200 through a resistor To. If the full output potential, is to be applied to the feedback path,

the potential divider may be omitted, and resistor. .ro connected directly from terminal-,2

towterminal 200.

As the amplifier shown. in Fig. 2 has an, odd number ofv stages when a potential of one :polarity with respect toground is connected to the .input terminal 200, the potential Withtrespect to ground of. the output. terminal 224 will be of t he opposite phase, that is, the amplifier reversesthe polarity .of the potential appliedtothjinput terminal 200.

Let a-source of voltage e1 be, connected through a resistorof resistance '11, t0,the inputterminal v24 10, let the potential difference 1 between the terminal 200 and ground, ber the potential difference ,between terminals 2,2'l, 225,,be Tel, the fraction of this potential applied ,to the feedback be -Ke, the resistance of the feedbackresistor bent and the voltage amplification of theamplifier be m.

The resistors 204, 2,05 impress a.,pos itive,bias ,on the cathode of thetwin triode ZZB thus the CQIltlOl electrode of the, twin .triode 2 26 will not draw any current. As ,the. amplifier .reverses the polarity with .respectto ground of the applied voltage a-c urrent 2' can flow from ground through thesource to 50,000, let m=40,000,-K =1 and let ro=r1, then that is, the output voltage is very nearly equal to the input voltage.

Let the maximum value of e be say 120 volts, then the maximum value of g=.003 volt. That is, viewed from the source e1, the input circuit appears to have .a very low impedance.

When K: 1, and as if rizrz ro, then -e is the sum of 21 and e-i.

Assume a grounded source of potential e1 is connected through a capacitor of capacity C and a resistor of resistance T1 to the terminal 200, and that e is small. Let i be the current from the source e1, then 1 e =m+ zdt and diflerentiating 1 E "dt c dz 1 1de time; are- Thus where 6:2-718 and e=Cro(% (1- e After the transient term has died down,

- e Gr a?- that is, the output voltage e is proportional to the first derivative, or rate of change, of the applied voltage 61.

If the current drawn by the load tends to reduce the output voltage of the amplifier, this reduction will cause a change in 8g which restores the output voltage to its original value. The amplifier thus acts as a constant voltage generator, and, viewed from the load, appears as a generator of very low impedance, generally as an impedance of about one ohm.

All of the amplifiers in the computer which are of the type shown in Fig. 2, are indicated by small triangles, the base representing the input circuit and the apex the output circuit, and are marked with a suitable symbol designating the quantity represented by the output voltage.

The sources I and M, Fig. 1, are of negative polarity, thus, due to the reversal of polarity,

I tance.

Range spot The output circuits of amplifiers 362, 306 are respectively connected to the contacts of switch 301. The blade of switch 30'! is connected through resistor 308 and the winding till of potentiometer PT9 to ground. The brush of potentiometer PT9 is connected through resistor 310 to the input circuit of amplifier 392. When the blade of switch 3M is on the left-hand contact, the output circuit of amplifier 392 is connected to ground through the winding of potentiometer PT9 and the voltage selected by the brush of potentiometer PTH and supplied to the input circuit of amplifier 3412 will be of opposite polarity to the voltage supplied to resistor 3l 5, thus reducing the output voltage of amplifier 302. On the other hand, when the blade of switch 381 is on the right-hand contact, the voltage supplied by the brush of potentiometer PT9 is of the same polarity as the voltage supplied to resistor 315 and increases the output voltage of amplifier 3il2. As the current supplied to the winding of potentiometer PTS is proportional to the slant distance, the change produced by any given setting of potentiometer PT9 will be proportional to the slant distance, thus, a scale, graduated in percentage of slant distance, may be associated with the brush of potentiometer PT9.

If desirable, the range spot may be arranged to change the slant distance by amounts expressed, say, in yards. The contacts of switch 3&7 are disconnected from the output circuits of the amplifiers 302, 3% and connected to the poles of a suitable source of power 3i i having an intermediat point grounded. In this case, a scale, graduated in yards may be associated with the brush of potentiometer PTB.

In Fig. 3c, 0 is the observation point, to the present position of the target, a the vertical projection of the target on the horizontal plane, Eo

the present elevation angle of the target, H0 the present height and R0 the present horizontal range of the target.

Then

Ho=Do sin E0 (4) R0:D0 cos E0 (5) The output circuit of amplifier 362, Fig. 3, is connected to ground through connection 312, fourth set of break springs of relay I9, Fig. 1, resistor 20, and the lower portion of the winding 583 of potentiometer PTE.

The output circuit of amplifier 365, Fig. 3 is connected to ground through connection 353, first set of break springs of relay I9, Fig. 1, and the upper portion of the winding 593 of potentiometer PT5. An intermediate point in the winding 503 is grounded.

The potentiometer cards may be made by winding resistance wire closely and evenly on a strip of insulating material. One edge of this strip is straight and the wire crossing this edge is cleaned to make a good contact with the brush; the other edge of the strip is shaped so that the width of the stripwill-vary to.-.produce" the ,de-

sired 1 functional .variation. in the resistance ,of the winding. 4A1 single .card,-.lor-..a. plurality-of cards. placed end. to $151,115: wrapped: :around, a light Ldrumpf. suitable..material,- a continuous binding ring is placed round the card, .orcards,

and wedges inserted .betweemthe ringnandi-card to -press the card firmly. to the F drum. Pr iplu- .on the intermediate portionof ,the...base, concentric with theshaft. brushes in contact with thestraight edges of the cards and connected toother brushes. in contact with the corresponding slip rings, are .mountedon .thepotentiometer shaft and maybedriven directly by theshaft, .or. by gearing supportedby thebase and meshing with gears mounted on theshaft and brusharms.

.In the circuit drawings, the cards of potentiometers which are automatically adjusted during the computations have been represented .circlessurrounded by arcs indicating approximately the variations. in the widths ofthe cards. Potentiometers which are preset .for .a given computation, or manuallyadjusted, are re resented by straight cards, though these cards may also be formed into circles ifdesired. Each potentiometer. has been given a PT number, e. g., PT23, and the associated cards numbered to correspond e, g.,.23H, 2392. etc.

;In the present'computer, angles are. measured inmi1s,.where,.6400 mils-is one revolution.

The brushes ,of. potentiometer PTE ,arerotated by the elevation, or pointer,.telescopesyrnboli- .cally represented by thetelescope 4- and associated gears. The card .563 extends over +1600 mils elevation and 200 .mils; depression, the grounded tap representing mil. or horizontal. The resistance. of the resistor -and. the lower .portion of ,thewindingis equal to the resistance ofthe upper portion of the. winding.

, The winding .of card533 has a sinusoidal-.varia- .tion of resistanceand, as the .voltage;supplied ,to the upper end of the card corresponding to 1600 mils, is proportional to -.Do and the voltage suppliedto resistor 2il;is,proportional to +130, the voltagesselected by thebrush associated-v with card 503. is proportional to Do .(-sin, E0) that. is,

"T[he,brush v associated withw card. 5.93 .is connected through resistor l6, secondzpa-ir ;of break springs of relay [9, connection I! to theablilde of switch 2|.

When ranging witha height finder, the synchronous transmitter driven by theheightv shaft of .the height finderis connected to the .syn- 'chronous receiver 1, driving the inner dial,, 8. Themotor I I, through the speed reducingdevice 23 drives the brush associated .withcard Bill, PT8, and through suitable gears, represented by gears 24,25, drives the middledial .9.

A grounded source of positivepotential. 25.is connected to ground through resistor .26 .and the winding of card Gill. The brush :of-.:card- 801 is connected through resistor. 2lpto the in ut circuit ofamplifier 28, having a feedback resistor 3|. The lefthand contact of switch. 2| ,is connected through resistor 29 to the input circuit of amplifier .28, and a suitable meter 39 .is ggnnected across the output oircuitlofflamplifier Brush. arms, carrying The operator. adjusts vthevdevice *23--until the dial 9 tracks the dial 8, thus causing thebrush .of potentiometer PT8 .tosupply a voltage tothe amplifier 28 proportional:to-+Ho. The-operator then-adjusts the. device .12 until the-:meter 30 reads .zero. The voltage supplied to resistor 29 is thus made proportional to-;Ho, .and;.as*the telescope 4 is tracking the target, the voltage selected by the brush of potentiometer PTB, will be proportional to Do, the slant distance to thet'arget.

In some cases, theheight finder may not be at the same elevation as the reference point of the battery and a correction in height is re- ;quired. A source 'ofpower "32; having an'intermediate point grounded, has both poles connected to the contacts of aswitoh 33. "The blade of switch 33 is connected to ground through'resistor and the winding of card 10!, FM. "The brush of potentiometer PTl is connectedthrough resistor 35 to the input circuit of amplifier 28. The switch 33 is set to select a-voltage of proper polarity, and the brush of. potentiometer PT! is adjusted to selecta voltage of proper magnitude, which, when supplied to resistor 35 will correst for the difference in height.

Altitude spot The brush, of potentiometer PT'I' maybe-adjusted to, produce. small arbitrary changes. in the voltage supplied to the amplifer." 28 whichlare equivalent tosmall changes in the ,voltagevse- :lected by the brush of -potentiometer:PT8.

When a height finder is noteused, switch. 2! may be placed on the right-hand contact, thus grounding connection .llwthrough resistor 22, which has a resistance equal to the resistance of resistor 29.

The output circuit of amplifier 306, Fig. 3, is connected by connection=3i3, break springs of first pile-up of relay l9, Fig. 1 to the junction of cards 50!, 502, potentiometer PT5. The outer end of card 50! isgrounded; and the outer end of card 532 is connected togground through resistor 35. Card 59! extends over an arc of 1600 mils; card 502 extends over an arc of 200'rnils; the resistanceof card 502 and resistor 36 being equal to the resistance of card 50!. The brush associated with cards 50 l, 502 is placed at a right angle with respect to the brush'associated with ,card 503, and-ds-movedby'the. movement of the telescope 4. The windings of cards WI, '502 have resistances varying .with a cosinusoidal function, and, as the voltage supplied by amplifier 306, Fig. 3, is proportional to --Do, the voltage selected by the brush associated with cards 50!, 5.02,.F-ig. .1, will be .proportional to ,Do (--+cos E0) that is, to -R0.

The brush associated with cards'50L-5fl2 is connected .th1ough. resisto1*- 31, breaksprings of .secondpileeup of relay .l 9, connection-.38, resistor 32s,; Fig. 3, to. .the input circuit of an amplifier 32!, Fig..3,.having a feedback resistori322. The output circuit of amplifier..32l (is connected through resistor 323 with the. input circuitof amplifier 324, having-a feedback resistor..325.

The output circuit of, amplifier 324wis connected by connection 326, breakspringsof secondpileup ofrelay. 39,. Fig. l, to .theupper junction of cards -l,-.402,,potentiometer 191%. The output circuit. of amplifier 32 I,..Fig. 3,. isconnected by connection 321, break springs of fourthpile-up of relay.'39, Fig. 1, to the-lower junction-of :cards 40!, 402, :PT4. Cards 4lll, 4il2 arearrangedon the; circumference .of a circle. I 

